I've been actively building links for 3-4 years and I can share some of my learnings.
1. There are no shortcuts.
Using shady "get links quick" schemes don't yield long term results.
2. Relationships and reputation matter.
Sure, you can outsource link building to a freelancer. But there is a certain reputation you build up when you exchange link with build building agencies and other link builders in the industry. Your name will be known and you'll build trust.
3. Relevance > Site metrics.
Some sites have inflated DR (e.g. software that embed their links in their tool), and some sites have inflated traffic (some sites that publish articles for irrelevant high traffic, low relevance keywords).
This won't help you in the long run. Prefer sites and specific pages that have super high relevance to your niche.
4. Write for us sites work well in the beginning.
There are tons of sites that accept guest publications. You can simply do a parameter search in Google, such as:
inurl:write-for-us marketing
However, keep in mind that anyone can pitch their content there. The more strict the guidelines, the better. It means they don't allow crap content to pass from other publishers either.
5. Do your own SEO outreach.
This doesn't have to be tedious or time-consuming, if you're using the right tools.
There are several SEO outreach software out there that you can use that automate prospecting, outreach sequence and even writing a personalized copy.
Some of the most used link building tools are Influno, Respona, BuzzStream, Hunter. Choose what fits with your flavor, but do your research before committing.
I don't claim to be an expert on link building, I am also continuously learning. Just sharing my 2 cents
